The present invention in general relates to an apparatus for producing a constant, linear mechanical force at varying speeds. In particular, the apparatus is adapted to produce a linear mechanical force to operate the main drive system of an apparatus for stacking battery plates and separators.
Ordinarily, when it is necessary to provide the type of varying speed linear mechanical force which is discussed herein, a piece of equipment well known in the art as a Geneva Drive is utilized. A Geneva Drive mechanism, however, is a relatively expensive structure and generally has a very complex mechanical arrangement.
It is, therefore, a basic object of the present invention to provide a simpler, less expensive and much more easily implemented arrangement which is capable of efficiently providing a motion similar to a Geneva Drive by producing periodic variations in the speed of the movement of a piston in a fluid-actuated hydraulic cylinder.
In cooperation with the fluid-actuated hydraulic piston cylinder, a pump is provided in the present invention for pumping fluid to the hydraulic piston cylinder, and a tank is provided for receiving fluid expelled during the operation of the piston cylinder. Also provided is a reversing valve for alternating the direction of fluid flow into and out of the hydraulic cylinder, and of key significance is a valve mechanism which is introduced between the pump and the hydraulic piston cylinder. This valve mechanism engages and is operated by the motion of the hydraulic piston cylinder so that the flow rate of the fluid entering the hydraulic cylinder is variably controlled in response to the movement of the hydraulic cylinder.